Anyone who had the same problem?
This is the original script from bootstrap 4, which also has bootstrap and tether with the same attributes (integrity and crossorigin) so, since it is pretty new, any kind of help will be very appreciated.

Thanks for all the postings, they really helped. I did roll my own version to give it some structure and make it easier to read and update. Use enqueue as normal, use script for CSS files with a false tag at the end so that it loads at the top. Though it can probably be simplified somewhat.

I just cracked this by accident. I've had to use conditionals on some CSS files for ancient Internet Explorer versions and figured I may as well try putting an array in the same wp_script_add_data function that I used. It works!